Compact Frequency Reconfigurable Antenna for LTE/WWAN Mobile Handset Applications

In this communication, a compact frequency reconfigurable antenna for LTE/WWAN mobile handset applications is proposed. The proposed antenna mainly consists of radiating elements and two PIN diodes. In addition, the antenna has a simple structure with a compact size of 36.5 × 10 mm2. This antenna operates in six modes, and each mode is given a different resonant pathway by adjusting the bias states of two PIN diodes. When PIN diodes #1 and #2 are in the ON and OFF states, respectively, the proposed antenna can cover the LTE700 (698-787 MHz) band by operating in mode 1. Moreover, the wide bandwidth in a higher band formed by combining modes 2 and 3 can cover the LTE2300 (2305- 2400 MHz) and LTE2500 (2500-2690 MHz) bands. When PIN diodes #1 and #2 are in the OFF and ON states, respectively, a resonant frequency in the lower band is formed by integrating modes 4 and 5. This can cover the GSM850 (824-894 MHz) and GSM900 (880-960 MHz) bands. When the two PIN diodes are in the ON state, the proposed antenna can cover the GSM1800 (1710-1880 MHz), GSM1900 (1850-1990 MHz), and UMTS (1920-2170 MHz) bands in operating mode 6.